Unitary sheath securing means for sensing brush contact devices



y 1965 A. B. BENSON 3,193,654

UNITARY SHEATH SECURING MEANS FOR SENSING BRUSH CONTACT DEVICES Filed July 16, 1965 INVENTOR. ALFRED B. BE NSON EATWQ/VZ) United States Patent 3,193,654 UNKTARY Sl-IEATH SECURING MEANS FOR SENSING BRUSH CONTACT DEVICES Alfred B. Benson, Endwell, N.Y., assignor to Sensing Devices, line, a corporation of New York Fiied July 16, 1963, Ser. No. 295,341 4 Claims. (Cl. 200-166) This invention relates to electrical sensing brushes, suitable for use in devices for electrically analyzing perforations in rapidly moving records.

It has heretofore been found that most desirable results may be obtained by the use of sensing brushes each having a plurality of wires, which wires are arranged in several groups; a ferrule or sheath being provided for securely retaining such wires in suitable relationship, and for maintaining electrical connection therewith.

It has also been found desirable that there shall be current paths, between the several wires and their associated ferrule, which paths are of substantially equivalent resistance.

Maintenance of each of the wires in its intended relationship with the ferrule has been found to be very important, because longitudinal movement of any wire in one direction will withdraw the active end thereof from the path of a record during its analysis, and thus destroy the intended usefulness of that wire; and longitudinal movement of any wire in the opposite direction, not only causes impairment of the sensing efiectiveness of near-by wires, but, of still greater importance is the fact that such displacement of any wire as will cause it to project beyond the other wires of its group, is likely to result in serious permanent impairment of the future utility of records so damaged during their analysis.

Sensing brushes have heretofore been constructed which utilized metallic ferrules cast around groups of brush wires, as exemplified by brushes shown in Patent 2,129,764 to Hayes; however the manufacture of brushes having cast metal ferrules has involved objectionably slow and hence expensive procedure.

For the purpose of overcoming the objectionably extensive time required, and'of the cost of producing brushes having cast metal ferrules, brushes have also been devised using ferrules formed of sheets of electric conductive metal, and containing two groups of wires, as exemplified by the brushes shown in Patent 2,716,684 to Barnes.

Rolled or extruded metallic sheets are shown by Barnes as being provided with a rib so situated that, after the sheet is bent into final form, channels are provided between the side walls of the ferrule and the respective sides of the rib, for receiving one and the other of two groups of wires.

When the ferrules shown by Barnes are bent into final form, strips of the metal sheet extend from respective side walls, and the adjacent edges of said strips meet midway between the two groups of wires and extend along the top of the rib.

It has been found that sensing brushes having sheet metal ferrules constructed as just described, will give very satisfactory service when they provide for two groups of wires. However, it has been further found that, when ferrules formed in accordance with the disclosure of said Barnes patent are used for an odd number of groups of wires, particularly for three side-by-side groups, there are problems other than such as are presented when provision is made for two groups of wires.

Thus, for example, to provide a sensing brush having three groups of wires, and utilizing a sheet of bendable metal, rolled or extruded so as to provide two ribs, which ribs are so positioned that two of the three groups of wires may be placed between respective side walls of the completed ferrule and the ribs respectively nearest thereto, and the third group placed between one and the other of said ribs, should the seam be situated midway between the side walls of the ferrule, such seam will extend above and parallel with the wires in that group which are midway between the two outer groups. Because of this, it has been found that one or another of such wires tend, during use of the sensing brush, to work into the seam after more or less use, and thereby serve to hold the strips away from the wires of the central group, as well as decreasing pressure upon the wires which are situated nearest the center group in the other groups; thereby permitting such wires to become displaced during use.

It will be apparent that if a ferrule having three groups of wires is so formed that the seam is disposed over one or the other of the ridges provided therein (as it is in ferrules having but two groups of wires), the closure strips will effectively hold the wires in the group between that ridge and the adjacent outer wall, while failing to effectively hold the Wires of the other two groups; and it is therefore an important object of this invention to provide a ferrule, of bent sheet metal, which will retain all of the wires in each of three groups as effectively as the wires of each of the two groups are held by prior two group sheet metal ferrules.

With this and other objects in view, this invention consists of features disclosed in the following detailed description, taken with the drawings, which show on enlarged scale for increasing clarity, sensing brushes embodying this invention, and in which:

FIG. 1 is an enlarged perspective view of a sensing brush constructed in accordance with one form of this invention.

FIG. 2 shows a sheet of metal suitable for being so bent as to provide the ferrule of the brush shown in FIG. 1.

FIG. 3 is an enlarged perspective view of a sensing brush constructed in accordance with another form of this invention.

FIG. 4 shows a sheet of metal suitable for being so bent as to provide the ferrule of the brush shown in FIG. 3.

The sensing brush shown in FIG. 1 comprises three separate, spaced groups of sensing wires, W1, W2, and W3; each of which groups consists of six flexible wire strands. Said wires are enclosed and securely retained in suitable relationships by the ferrule F.

The piece of pliable, ductile metal 12, shown in FIG.

2, is suitably formed and bent around said wire strands,

and comprises the ribs R1 and R2; however, it should be understood that detached metal bars may be utilized in place of having the ribs R1 and R2 formed integral with the piece 12 without departing from other features of this invention. Nevertheless, it is believed that most rapid assembly and satisfactory results will be obtained if such ribs are integral with said piece 12.

The grooves G1, G2, G3, and G4 may be formed in said metal piece 12 in order to facilitate its being so bent as to provide the ferrule F. The spacing of the grooves G1 and G2 from the ribs R1 and R2, respectively, is such that, when the said piece 12 has been bent along these grooves, left hand and right hand side walls 1 and 2 will be provided; and that when so bent, there will be channels between said walls 1 and 2 and their respectively associated ribs R1 and R2 such that the wire groups W1 and W3 may be firmly held therebetween.

The portions of the sheet metal piece 12 which extend beyond the grooves G3 and G4, provide the strips S2 and S1 which, after the completion of the bending of the piece 12, complete the enclosure of the wire groups W1, W2, and W3.

The edges 21 and 22 of the strips S1 and S2, respectively, are so relatively formed that, after aforesaid com pletion of the bending of the ferrule, said edges will meet to form a seam' 23, which seam extends from the lower edge ofithe ferrule, at a point to the left of the wire group W2 (as viewed in FIG. 1) V and terminates at the one edge of which ferrule said wires extend; one of said groups being spaced from one and the other thereof by structure situated within said ferrule and extending parallel with said wires, said ferrule being formed from a sheet of resilient conductive material of such shape and so wrapped around said wires that meeting of adjacent edges of said sheet form a seam which extends from one to the other of the edges of said ferrule and traverses all r of the wires of said one of said groups.

2. A combination as defined in claim 1 wherein said seam traverses all of the wires of the intermediate group the bending of the various portions of the ferrule have 5 been completed, theupper surfaces of said ribs will be, situated below the under surfaces of the bent over strips 51 and S2, to an appreciable extent, but to an extent distinctly less than one-half of thediameter ofthe wires 7 to the endthat, after completion of the ferrule, none ofa said wires canescape the channel which is provided for its group, by partially or fully passing between the top of the adjacent rib and the under surface of'the associated bent-over strips S1 or S2. 7 y

After the completion of the aforesaid'various bending operations, one or more deformations, such as thedeformation25, may be pressed into the strips S1 and S2, for the purpose of moresecurely maintaining the intended relationships between the wires of said groups.

The sensing brush shown in FIG. 3 differs from that 0 shown in FIG.- .11 in that the'edg'es '21 and 22" of the strips S1. and S2, respectively, are so relatively formed that, after completion of the bending of the ferrule, said edges will meet'toform a seamZS', which extends from a position over the. lower end of the rib R1 (as viewed vin FIG. 3) to a position between the ends of the ferrule- F (shown as approximately midway) and there crosses to the rib R2, and terminates over the upper end of said rib asso viewed. a

From the foregoing it will be evident that, sensing brushes having sheet metal fe-rrules,.may be. constructed pursuant to this invention, which providefor securely holding each of the wires of three groups, the wires of of the three side-by-si de groups of contact wires.

7 3. In an electrical sensing brush, the combination of three side by-side parallel groups of contact wires and an elongated sheathing ferrule; securely retaining said groups of wires therein and from one end of which ferrule said wires extend; said parallel groups being spaced from one and the other thereof by structure situated within said ferrule and extending parallel with said wires, said ferrule being formed from a sheet of, resilient conductive material of such shapeand so wrapped around said wires that meeting of adjacent side edges of said sheet'form a seam which extends from one to" the other of the end edges of said ferrule'at an angle to the parallel groups of wires 1 and which seam traverses all of the wires of the intermediate of said groups of wires.

4. In an electrical sensing brush, the combination of three side-by-side parallel groups of contact wires and an elongated sheathing ferrule securely retaining said groups of wires therein and from one end of which ferrule said wires extend; said parallel groups, being spaced from one and the other thereof by structure situated within said ferruleand extending parallel with said wires, said ferrule being formed from a sheet of resilient conductive mate- .rial ofYsuch shape and so wrapped aroundsaid wires that meeting .ofadjacent side edges ofsaid sheet form a seam which extends-continuously. from onelend' of the ferrule to therother, said seam being characterized by two longitudinal sections thereof each originating at a remote the two of such groups which are situated between the side walls of the ferrules and the ribs nearest thereto,

respectivel, being securely retained in position by ap-" plication of: all of the force which'c'an be applied'by the respective ones of the bent-over strips.

What I claim as my invention and desire to secure by 7 United States Letters Patent is: a

1. In an electrical sensing brush, the combinationof .t-hree sidesby-side groups of contact wires and a sheathing ferrule securely retaining said wires therein and from end of said ferrule and extending half the length thereof in offset relationvon opposite sides of the intermediate group of wires, and said seam sections being joined intermediate the length of said ferrule by a perpendicularly transverse section thereof overlying and traversing the intermediate group of said groups of wires.

References Cited by the Examiner e j 'UNITED STATES PATENTS 7 2,093,198 9/31 Kleinmann 200-466 ATHLEEN'H. CLAFFY, Primar y Examiner.

BERNARD AVGILHEANY, Examiner. V 

1. IN AN ELECTRICAL SENSING BRUSH, THE COMBINATION OF THREE SIDE-BY-SIDE GROUPS OF CONTACT WIRES AND A SHEATHING FERRULE SECURELY RETAINING SAID WIRES THEREIN AND FROM ONE EDGE OF WHICH FERRULE SAID WIRES EXTEND; ONE OF SAID GROUPS BEING SPACED FROM ONE AND THER OTHER THEREOF, BY STURCTURE SITUATED WITHIN SAID FERRULE AND EXTENDING PARALLEL WITH SAID WIRES, SAID FERRULE BEING FORMED FROM A SHEET OF RESILIENT CONDUCTIVE MATERIAL OF SUCH SHAPE AND SO WRAPPED AROUND SAID WIRES THAT MEETING OF ADJACENT EDGES OF SAID SHEET FORM A SEAM WHICH EXTENDS FROM ONE TO THE OTHER OF THE EDGES OF SAID FERRULE AND TRAVERSES ALL OF THE WIRES OF SAID ONE OF SAID GROUPS. 